#include <deque>
#include <iostream>
#define int long long
using namespace std;
unsigned int T;
deque<int> deq;
signed main() {
  	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
  	cin >> T;
  	while (T -- ) {
  		int op, x, k, c;
    	cin >> op;
    	if (op == 1) {
      		cin >> x;
      		deq.push_front(x);
    	}
		else if (op == 2) {
      		cin >> x;
      		deq.push_back(x);
    	}
		else if (op == 3) deq.pop_front();
    	else if (op == 4) deq.pop_back();
    	else if (op == 5) {
      		cin >> k >> c;
      		unsigned int cnt = 0;
      		int sum = 0;
      		for (auto i = deq.begin(); i < deq.end() && cnt < c; i += k) {
        		++ cnt;
        		sum += *i;
      		}
      		cout << sum << "\n";
    	}
		else {
      		cin >> k >> c;
      		unsigned int cnt = 0;
      		int sum = 0;
      		for (auto i = deq.rbegin(); i < deq.rend() && cnt < c; i += k) {
        		++ cnt;
        		sum += *i;
      		}
      		cout << sum << "\n";
    	}
  	}
  	return 0;
}